Statistics based on reported offenses and victimization surveys indicate that sexual crimes are increasing at an alarming rate. Though the conviction rate for sex offenders is low, there is growing concern about what should be done wih offenders who have been turned over to the correctional system. Very few offenders receive treatment directed specifically toward their sexual problems. But, in 12 states and one Canadian province, comprehensive programs designed expressly for this purpose do exist. Thus far, the effectiveness of these programs has not been adequately assessed. The primary purpose of this project is to plan for an evaluation of 6 to 8 institutional sex offender treatment programs. Planning activities will include (a) site visits to selected institutional programs and to prisons and community-based programs that could serve as potential comparison sites: (b) identification of feasible evaluation designs; (c) delineation of program objectives, components, and criterion measures; (d) a meeting of program representatives, staff of the Center for Prevention and Control of Rape, and the investigators; (e) resolution of critical issues involving human subjects; (f) selection of an evaluation management system; and (g) preparation of an evaluation project proposal. The subsequent evaluation project to follow the planning period should (a) demonstrate the relative effectiveness of existing sex offender treatment programs, (b) contribute to modifications of the various treatment models, and (c) provide policy relevant information to facilitate program development in states without treatment options.